Hormones play a preeminent role in control of female reproductive processes; however, accumulating evidence indicates neural mechanisms, including afferent, efferent and central connections, are involved in reproductive processes, e.g. neuroendocrine reflexes, blood flow, smooth muscle control, sex steroid secretion, and parturition. Denervation of reproductive organs produces dysfunctions such as disrupted estrous cycles, decreased sex steroid secretion, implantation failure and prolonged gestation. Explanations of such problems are hampered by lack of fundamental information about the neurochemical anatomy of vascular, smooth muscular and glandular control and sensory reflexes in reproductive organs, e.g., the neurochemical anatomy of local sensory reflexes in reproductive organs, e.g., the neurochemical anatomy of local autonomic ganglia in pathways to genital organs is not well understood. Paracervical ganglia (PG) provide parasympathetic innervation to reproductive organs. Collaterals of primary sensory nerves ramify among PG neurons so these neurons could be influences not only by preganglionic nerves, but by sensory nerves as well. It is hypothesized that collaterals of peptide- containing sensory nerve fibers can interact with, and influence specific components of the female reproductive organs. Aims of this proposal are to extend current studies of the chemical neuroanatomy of the PG and their innervation of reproductive organs by examining sensory nerve- parasympathetic interactions in the PG. Using immunocytochemistry, double labeling, electron microscopy and axonal tracing methods we propose to address three specific objectives: #1 characterize in the PG the presence, distribution and source of and colocalization patterns of peptides in chemically-coded sensory nerves immunoreactive for substance P, neurokinin A, calcitonin gene-related peptide and galanin; #2 examine synaptic characteristics of the interactions of the peptidergic sensory nerves with PG neurons; #3 determine any patterns of association between these chemically-coded sensory nerves and PG neurons chemically-coded for NPT, VIP, acetylcholine and noradrenaline. This study will provide data to help design future experiments examining functional influences of nerves on reproductive processes, elucidating effects of hormones on the peripheral neurons innervating reproductive organs and defining functional components mediating neural-endocrine- reproductive end-organ reflexes.